Modular Systems Combine Performance and Flexibility

Driven by intense cost and competitive pressures, semiconductor producers try to maximize production while improving outgoing quality. They also need flexible equipment that can be updated quickly and cost-effectively. Maximizing throughput measured in units per hour (uph) and doing it in the smallest area possible helps speed return on investment in an extremely competitive environment.

By Kevin Steele, Bosch Rexroth Corp. November 1, 2007

Driven by intense cost and competitive pressures, semiconductor producers try to maximize production while improving outgoing quality. They also need flexible equipment that can be updated quickly and cost-effectively. Maximizing throughput measured in units per hour (uph) and doing it in the smallest area possible helps speed return on investment in an extremely competitive environment.

One of the top manufacturers of inspection and packaging equipment for the semiconductor and electronics industries, International Product Technology Inc. (IPT) Systemation of New Berlin, WI, recently launched a high-performance integrated circuit (IC) inspection and packaging machine under its Systemation brand with throughput up to 15,000 uph. The ST-868 Handling System can handle inspection and packaging of several device form factors, such as ball grid arrays (BGA), quad flat pack (QFP), and micro-BGA (QFN,

One of the new system’s most important features is its modular design. Modularity allows a user of the equipment to easily reconfigure or update it by swapping out only the affected modules, rather than having to replace the whole machine. This capability saves time and money while extending the overall machine’s service life.

“Virtually every component, other than the machine frame, can be assembled and tested in isolation,” said Rob Bertz, vice president of engineering for IPT. “There are three major benefits gained from this practice: The first is that the machine modules can be outsourced to qualified manufacturing partners who can deliver tested modules to the final system integrator. This greatly reduces the time and cost to bring a new machine online.

“The second benefit is that the modular components can be reconfigured in new ways to create entirely new machines. This will reduce the cost and response time for future developments.

“The third modularity benefit is that if one of the modules is radically improved, it can be easily replaced by a new revision or module.”

Faster ROI

Machine modules include pick-and-place modules, four independent tray stacker modules, and taper modules. Each module has its own unique operational specification, and each has its own unique motion control node onboard. Every aspect of machine development, deployment and management over the lifetime of the machine can be done independently, at a modular level, as though it is a complete machine.

According to Bertz, the ST-868 dramatically changes the productivity equation for back-end inspection and packaging. Modularity of the motion control system is a critical element, enabling distributed self-contained intelligence for every sub-system. The result is a 50% increase in handling-system speed.

“Basically, one ST-868 machine can deliver the same production as two previous-generation machines,” Bertz reports. “By leveraging the motion control advantage plus maximizing packaging process efficiency, Systemation is able to provide a 100-percent increase of uph per square foot of plant floor space.”

The system also includes an advanced optional visual inspection feature called AVS DefectZero Inspection Technology, developed by IPT. It provides thorough end-of-line quality assurance with redundant device inspection at tray and tape outputs.

Optional inspection sites are selectable and may be configured to provide comprehensive defect detection on all six surfaces of all package types, with real-time remote access to inspection results. This remote access feature means results from every inspection machine on the test floor can be viewed from a central workstation, or even from another location.

Motion control, machine output

IPT achieved this throughput in part by using the FirePoint IEEE 1394 motion control solution from Bosch Rexroth. This platform uses a distributed, scalable architecture built around the high-speed FireWire backbone to support up to 20 axes of control per machine. These motion axes include the lift, rotation, inspection and packaging functions of the ST-868.

The FirePoint system uses a distributed architecture and modular components to give machine builders an “out-of-the-box” solution. It provides fully configurable I/O and functional nodes networked via high-speed FireWire backbone to an industrial PC. Each node’s functionality is user-programmable, and is capable of controlling digital and analog I/Os, servo motors and stepper motors. In addition, other FireWire devices like intelligent cameras can be integrated into the control architecture.

The distributed architecture and high-power FireWire backbone make the platform scalable from one up to 62 intelligent control nodes. Since the control nodes for each machine module are user programmable, changing or upgrading a specific machine module does not require rebuilding or replacing the entire motion control platform, just the node associated with that specific module.

For example, a tray stacker holding ICs to be packaged is a modular component whose axis of motion is handled by one control node. If, for example, the tray stacker must be replaced with new media, that module can be replaced separately. The machine still retains the other components.

The FirePoint platform was designed specifically to support high-speed motion and vision control systems using the IEEE 1394 network. Any IEEE 1394 compliant modules can co-exist on the same network.

FireWire is a high-performance serial bus with a real-time deterministic architecture that supports throughputs of up to 400 Mbps, which is suited to very fast, multi-axis applications.

Modular, fast

Choosing a modular platform for the ST-868 also provided other benefits: faster machine development, flexible end-user options, and an overall reduction of the footprint on a factory floor by achieving high output.

The platform comes with an extensive library of motion control tools and commands to enable faster commissioning and testing of machines. These C and C++ libraries eliminate much of the motion control programming burden that previous generations of motion control platforms required. This lets tool builders like IPT spend less time programming motion control and more time on the specific machine functionalities that provide their strategic advantage.

The platform’s physical design is also optimized for flexibility. The node units are modular and compact, engineered to conserve space. Standard units are DIN-rail mountable; however, rackline mountable or bare-board versions are also available, depending on an end-user’s requirements. This modularity helped IPT design the ST-868 to be very compact.

As industry needs evolve, the modularity of ST-868 prevents machine obsolescence and protects the end-user’s investment. New IC packaging formats, demands for higher levels of throughput, and new IC inspection requirements can arise every three to four years. To protect the long-term investment and ensure the machine meets future potential industry requirements, some of the ST-868 modules have been designed and tested to handle throughput rates up to 32,000 units per hour, if that level of processing is ever demanded. And, the FirePoint motion control platform modules have been tested and proven to support closed-loop sequences at the higher uph rate.

Instead of retiring the ST-868 and buying or building new equipment as needs change, the end-user can easily modify only those machine modules– the pick-and-place module, or the feeder modules, etc. – that need to be updated to current requirements.

Author Information
Kevin Steele is semiconductor and medical branch manager at Bosch Rexroth Corp.—Electric Drives and Controls. Reach him at .